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961.
962.
963.
A population-based surveillance for typhoid fever was conducted in three rural communes of Dong Thap Province in southern Vietnam (population 28,329) for a 12-month-period starting on December 4, 1995. Cases of typhoid fever were detected by obtaining blood for culture from residents with fever > or = 3 days. Among 658 blood cultures, 56 (8.5%) were positive for Salmonella typhi with an overall incidence of 198 per 10(5) population per year. The peak occurrence was at the end of the dry season in March and April. The attack rate was highest among 5-9 year-olds (531/10(5)/year), and lowest in > 30 year-olds (39/10(5)/year). The attack rate was 358/10(5)/year in 2-4 year-olds. The isolation of S. typhi from blood cultures was highest (17.4%) in patients with 5 to 6 days of fever. Typhoid fever is highly endemic in Vietnam and is a significant disease in both preschool and school-aged children.  相似文献   
964.
目的比较经额部与经颞部血肿钻孔引流术治疗高血压脑出血的疗效。 方法按照制定的检索策略,检索中国知网、万方、维普等中文数据库及Medline、Embase、Cochrane等英文数据库,对于符合纳入排除标准的研究利用RevMan 5.3软件进行Meta分析。 结果经检索,5个临床研究符合标准,共488例病例,其中经额部钻孔引流组236例,经颞部钻孔引流组252例。2组在手术时间、术后第7天血肿残余量及术后并发症发生率方面比较差异无统计学意义,经额部钻孔引流组在术后第3天血肿残余量、住院时间、术后日常活动能力方面更有优势。 结论经额部血肿钻孔引流较经颞部在血肿清除效率、改善预后方面更有优势。  相似文献   
965.
BACKGROUND: An ectopic opening of the common bile duct in the duodenal bulb is extremely rare, and the clinical significance of this anomaly has not been clarified. This study analyzed the clinical implications and cholangiographic findings of this anomaly. METHODS: A total of 18 patients (15 men, 3 women; median age, 51 years) with an ectopic opening of the common bile duct in the duodenal bulb were studied. Medical records, endoscopic findings, and cholangiographic and other radiographic findings were reviewed. RESULTS: All 18 patients had biliary pain; 7 had fever and chills. Fifteen (83%) had diffuse dilatation of the extrahepatic bile ducts with or without intrahepatic bile duct dilation. Associated bile duct stones were found in 10 (56%) patients. The papilla in the bulb had an orifice stained with bile at endoscopy, which was associated with duodenal ulcer disease found in 13 (72%) patients. The distal end of the common bile duct was tapered and narrowed and had a hook shape in all patients. CONCLUSION: An ectopic opening of the common bile duct in the duodenal bulb may be associated with clinical entities such as recurrent or intractable duodenal ulcer, choledocholithiasis, or acute cholangitis. Although these openings are rare, knowledge of the endoscopic and radiographic findings of an ectopic opening of the common bile duct in the duodenal bulb may help to clarify the cause of chronic recurrent duodenal ulcer disease in some patients and prevent damage to the bile duct during surgery.  相似文献   
966.
INTRODUCTION: Sustained atrial fibrillation (AF) is frequently encountered during pulmonary vein (PV) isolation. The aim of this study was to evaluate the feasibility and safety of PV isolation during sustained AF. METHODS AND RESULTS: Thirty-seven patients (30 men, age 54 +/- 10 years) underwent Lasso-guided isolation of 87 PVs during sustained AF. Baseline PV electrogram patterns were classified into one of two types: organized, with consistent PV activation sequence; or disorganized, with constant variation of PV activation sequence. In disorganized activity, radiofrequency ablation was performed circumferentially around the Lasso while the earliest PV potential was targeted during organized activity. Complete left atrial (LA) to PV block during AF was identified by abolition or dissociation of all sharp potentials recorded within the vein. PV isolation then was verified during sinus rhythm. Baseline activation patterns of PV potential were organized in 32 PVs (37%) [more frequently in inferior veins than superior veins (53% vs 26%, P = 0.01)] and disorganized in 55 PVs (63%). In 59 of 87 PVs, isolation was begun and completed during AF. Radiofrequency ablation organized PV activation sequence in 75% prior to isolation. LA-PV block was confirmed during sinus rhythm in 54 (92%) of 59 PVs. In 28 of 87 PVs, sinus rhythm was restored before complete LA-PV block. Complete isolation was achieved in all 87 PVs without complications. CONCLUSION: PV isolation can be effectively and safely performed during sustained AF, preceded in most cases by organization of PV electrogram activity. This strategy may be the preferred alternative to multiple intraprocedural cardioversions.  相似文献   
967.
Life-threatening cardiac tamponade is one of the most serious complications of catheter-based cardiac procedures. Although most cases can be effectively treated by percutaneous pericardiocentesis, urgent surgical drainage is required in unsuccessful cases. Rarely, in collapsed patients, the delay for surgery, however minimal, may be fatal. We describe a technique whereby life-saving pericardial drainage was rapidly achieved via a novel transcardiac approach, using the transseptal puncture kit, after failure of conventional pericardiocentesis in a patient with procedure-related acute tamponade who rapidly deteriorated and developed cardiorespiratory arrest within a few minutes. Although surgical repair for the perforation had to be performed subsequently, the patient survived without sequelae. This transcardiac approach may be an important and potentially life-saving adjunctive technique after failure of conventional pericardiocentesis in rapidly deteriorating or extremely unstable patients.  相似文献   
968.
BACKGROUND: The use of percutaneous endoscopic gastrostomy (PEG) for enteral nutrition in patients admitted for stroke is difficult, varying and needs specific consideration. There is therefore need for more data on this patient group. We examined the indications, survival, tube removal and time with PEG in stroke patients and in other patients with PEG with the aim of providing guidance for the management of enteral nutrition via PEG in stroke patients. METHODS: Retrospective assessment of data from all stroke patients and patients with other diseases (control group) who had received PEG for enteral nutrition during a period of 8.5 years. RESULTS: Eighty-three stroke patients with dysphagia received PEG after unsuccessful use of nasogastric tubes or long-term tube feeding. Early mortality rate was 19% in the stroke group, 26% in the older group (>74 years) and 12% in the younger group (60-74 years). The PEG tubes were later removed due to swallowing recovery in 20% of the older group and in 31% of the younger group. At 90 days, 50%-60% still needed PEG. The stroke patients were older compared to the control group (n = 115); 30-day mortality was similar but more patients recovered the ability to swallow. CONCLUSIONS: Stroke patients are older than other patients who receive PEG; 27% have swallowing recovery and more than 75% have long-term need for PEG. Nasogastric tubes often fail, and the need for early PEG placement (within 2 weeks) must be assessed in appropriate patients. The patient's prognosis, the objective of nutritional treatment, duration of dysphagia, age and comorbidity should all be taken into consideration.  相似文献   
969.
MurG is an essential glycosyltransferase that forms the glycosidic linkage between N-acetyl muramyl pentapeptide and N-acetyl glucosamine in the biosynthesis of the bacterial cell wall. This enzyme is a member of a major superfamily of NDP-glycosyltransferases for which no x-ray structures containing intact substrates have been reported. Here we present the 2.5-A crystal structure of Escherichia coli MurG in complex with its donor substrate, UDP-GlcNAc. Combined with genomic analysis of other superfamily members and site-specific mutagenesis of E. coli MurG, this structure sheds light on the molecular basis for both donor and acceptor selectivity for the superfamily. This structural analysis suggests that it will be possible to evolve new glycosyltransferases from prototypical superfamily members by varying two key loops while maintaining the overall architecture of the family and preserving key residues.  相似文献   
970.
为了探讨半边莲对动脉内皮保护作用的有效成分 ,提取半边莲两种不同组分用于高脂血症大鼠 ,观察对动脉内皮细胞内皮素和内皮源一氧化氮合酶代谢以及对动脉内皮功能和形态的影响。结果发现 ,高脂血症大鼠应用半边莲B0 0 1组分 6 0天后 ,血浆内皮素浓度和动脉内皮细胞内皮素阳性细胞率明显低于高脂未用药组 (P <0 .0 5 ) ,血浆内皮源一氧化氮合酶浓度显著高于高脂未用药组 (P <0 .0 5 ) ,且动脉内皮损伤减轻 ,但血脂无明显变化。应用半边莲A0 0 1组分的高脂血症大鼠血脂浓度、内皮素和内皮源一氧化氮合酶无明显变化。结果提示 ,半边莲B0 0 1使高脂血症时内皮细胞、内皮素合成及释放减少 ,并可促进内皮源一氧化氮合酶的合成 ,缓解高脂血症对血管内皮的持续损伤。  相似文献   
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